Dripless plastic pour spout insert

ABSTRACT

An improved insert for permanent or removable mounting in the outlet opening of a container having a pouring spout has a surface of fluoro carbon polymer, whereby aqueous liquids such as hot coffee and tea may be poured without spilling drops. The insert may have any desirable shape which fits into the spout.

Q United States Patent 1191 1111 3,868,051

Goof Feb. 25, 1975 [54] DRIPLESS PLASTIC POUR SPOUT INSERT 233,042,195 741962 Richmond.i 222/570 ,lO ,086 10 l963 Russell et a.. 17 138.8 VF [761 Invent Karl Lemar! 236 A 3,113,693 12/1963 Stull 222/570 ux Gammel Strandrq. 3050 3,120,908 2/1964 Szajna et al.... 222/570 x Huml ba q mfa k 3,122,287 2/1964 Makowski 222/570 x 3,129,020 4/1964 Bujnowski 222/570 X [221 Med 1972 3,253,753 5/1966 Barton etal. 222/569 x [21] Appl. No.: 226,956 3,282,478 11/1966 Russell 222/569 X Primar Examiner--Stanle H. Tollber 30 F A 1 t P 1 1) Y Y 8 1 F b fg I y y ata 7 Assistant Examiner-Norman L. Stack, Jr.

e enmar Atto ney, Agent or irm Flynn & Frishauf 52 us. 01. 222/571 [51] Int. Cl B67d 5/74 [57] ABSTRACT [58] Field of Search 222/570, 567, 571, 569; A f b Uri/138.8 VF n improved insert or permanent or remoya le mountmg 1n the outlet opening of a contamer having a [56] References Cited pouring spout has a surface of fluoro carbon polymer, whereby aqueous liquids such as hot coffee and tea UNITED STATES PATENTS may be poured without spilling drops. The insert may 2,834,521 5;]958 Elyfien 2221570 X have any desirable shape which fits into the spout. 2,979,239 4 l96l 0 ins 3,029,987 4/1962 Gronemeyer 222/569 X 13 Claims, 4 Drawing Figures PATENIED FEBZ 51975 PRIOR A FIG.2

DRIPLESS PLASTIC POUR SPOUT INSERT BACKGROUND OF THE INVENTION It is known to provide bottles and similar containers having a cylindrical or substantially cylindrical pouring spout with a dropprotecting body of plastic which is elastic and which shows moderate hydrofobous properties. Said body may consist of a portion which can be pressed down and fit into the outlet opening of the bottle. and a flange portion being integrally moulded with said first portion and extending substantially perpendicular to a longitudinal bore in said first portion. An insert of this type is shown in FIG. 1 of Swedish Pat. No. 207,742 issued to A. B. KABO PLASTIC INDUS- TRI, Bandhagen. An insert of this type is not reliable as a means for preventing spilling of drops, since there is a tendency to build up a drop of increasing size by successive pourings of aqueous liquids.

In order to avoid this disadvantage it is proposed in the abovementioned Swedish patent to provide the body with a cylindrical upper portion extending from the inner edge of said flange portion and substantially perpendicular to said flange portion. By embodying a sharp top edge on said upper cylindrical portion, a body has been provided which functions in a reliable way in regard of protection against spilling of drops.

This drop-protecting body of the prior art has a pure functional appearance which limits its utility to such bottles and containers where the appearance of the body is not in conflict with aesthetic and architectural requirements. The known body will therefore be most suited for bottles for beer, lemonade and mineral water and wine, where in most cases it is without any importance that the body has a shape, which is conditioned by the function. In other cases such as in particularly designed containers, such as for example teapots and coffeepots, it is not desirable to use such a body having a functional shape, because this shape is not in harmony with the design of the container. In order to protect such specially designed containers against spilling of drops the prior art spouts have been embodied in a particular way, in particular by embodying means in the spout which have capillary effects. Such means makes these containers more expensive, and they are difficult to clean.

SUMMARY OF THE INVENTION The invention relates to a drop-protecting insert for permanent or removable mounting in the outlet opening of a container having a pouring spout and it is the purpose of the invention to provide such an insert which may have any desirable shape, but still is able to protect effectively against spilling of drops.

This is obtained according to the present invention by making at least that part of the insert which the liquid by pouring ultimately will be in contact with, of polytetrafluoroethylene or a similar fluorocarbon polymer.

The term insert or liner is intended to be understood in its broadest sense and it includes for example a surface coating on the pouring spout which only needs to be present on that part ofthe spout with which the liquid ultimately or terminally is in contact with.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a liner configuration according to the prior art in which the shape or form thereof is critical;

FIG. 2 illustrates an insert or liner according to the present invention made of a fluoro carbon polymer;

FIG. 3 illustrates another embodiment of an insert or liner according to the present invention; and

FIG. 4 illustrates an embodiment of the the present invention wherein the liner is in the form of a surface coating on a container spout.

DESCRIPTION OF PREFERRED EMBODIMENTS It has surprisingly been found that pouring spout inserts of polytetrafluoroethylene, even after a plurality of successive pourings, prevents build up of a drop which may be spilled for example on table or cloth. This effect of the plastic in question has been found to be essentially independent of its outer shape. The container designer may therefore design his container without any risk that means which shall protect against spilling negative of drops will have a negative influence on the appearance of the container. The independency of the shape of the insert is particularly pronounced when the liquid to be poured is hot such as hot tea or coffee and the claimed insert will therefore be particularly useful for teapots and coffeepots.

It is known to the skilled person that polytetrafluoroethylene and similar fluoro carbon polymers have low friction and very low absorption of water, but still he should expect that an insert made of such material only could prevent spilling of drops, if it had a special shape. Here it should also be considered that the prior art has taught that the shape of the insert was of prevailing importance for preventing spilling of drops.

Referring to FIG. 1, there is shown a liner 1 which is inserted in.a spout 2 of a pouring vessel. In liner 1, the shape is of critical importance and a droplet 3 is shown on the lefthand side thereof to illustrate the operation of such a liner configuration. The liner 1 is removably inserted in the spout and has projecting portions 4 thereon to insure a tight fit within the spout and to pre vent leakage around the interface between the liner and spout. As discussed above, such prior art liners are undesirable since the spilling of the liquid is still a prominent occurrence. In accordance with the present invention, the liner configuration is formed of a fluoro carbon polymer, and it has been found by the present inventor that when such materials are used, the shape of the liner is not critical.

FIGS. 2 and 3 illustrate typical liner configurations fabricated of fluoro carbon polymers, such as polytetrafluoroethylene, in accordance with the present inventron.

The liner"5 of FIG. 2 has a flat upper surface 6. A rim or flange-shaped portion 7 extends outwardly over the terminal edge of the pouring spout 8 of a liquid containing vessel such that when the liquid leaves the terminal end of the pouring spout it contacts only the terminal of the liner 5, and not the spout 8 per se. Peripherally projecting portions 9 are provided to obtain a liquid-tight fit between the liner 5 and spout 8.

The liner 10 of FIG. 3 is another preferred form of the present invention. The liner 10 has a curved terminal surface 11 which terminally contacts the liquid leaving the spout 8. Other than the shape of the surface 11, the liner 10 of FIG. 3 is identical to liner of FIG. 2.

FIG. 4 illustrates a surface coating 12 of a fluoro carbon polymer (such as Teflon) at the terminal portion of a pouring spout 13 of a vessel. Again, the last element the liquid contacts as it leaves the vessel and spout is the coating 12.

Further advantages obtained by selecting a fluoro carbon polymer are that this material resists thetemperature of hot beverages, it can be cleaned in an automatic dish washer and it is not discolored by the ingredients of tea and coffee. Polyethylene, of which the known drop-protecting bodies usually have been prepared, does not possess these properties. Although fluoro carbon polymers are relatively expensive, it will be appreciated that they have such advantages which easily compensate for the extra expense in proportion to conventional plastic materials.

The term polytetrafluoroethylene and similar fluoro carbon polymers is intended to comprise such fluorocarbon polymers which possess similar properties as polytetrafluoroethylene, in regard to aqueous liquids. The selection ofa specific polymer including molecular weight, crystallinity and other properties resulting from the way in which it is manufactured can be made by the skilled person, and shall therefore not be discussed herein.

As previously mentioned the insert may be permanently mounted in the outlet opening of a container, and it may therefore be elaborated as a surface coating which is a per se known way may be applied as a step in the manufacture of the container, for example by a sintering step. This results in a configuration such as illustrated in FIG. 4.

When the insert shall be removably mounted in a container it may comprise a body having a longitudinal bore and fitting in a liquid tight manner in the spout of the container. That portions of the body which fits into the spout may in a manner known per se be provided with retention means such as lips, O-rings or other projecting means. See FIGS. 2 and 3.

Although, the drop-protecting effect as mentioned is essentially independent of the shape of the insert, practice has shown that a rough surface under extreme pouring conditions may lead to spilling of drops on table or cloth. The requirements related to smoothness of the surface can be reduced, if the insert has a plain surface on the outlet side of the outlet opening, and in particular when said plain surface is substantially perpendicular to the pouring direction and forms a sharp edge with the outlet opening.

Although, it is only that portion of the insert which ultimately is in contact with the liquid which has to be covered by a fluoro carbon polymer it is convenient for facilitating the manufacture that the whole insert is prepared from a fluoro carbon polymer.

That which is claimed is:

1. A liner for use in the outlet end opening of a container having a pouring spout, and for use in pouring of aqueous liquid, said liner covering a terminal end of said spout and being located such that at the terminal end of the spout said liquid when poured terminally contacts only the liner, the improvement wherein at least the surface of that part of said liner which said liq- 5 uid by pouring terminally is in contact with consists essentially of polytetrafluoroethylene.

2. A liner according to claim 1 including means for removable insertion thereof in the outlet end opening of said container pouring spout.

3. A liner according to claim 1, said liner being permanently mounted in the outlet end opening of said container pouring spout.

4. A liner according to claim 1, said liner comprising a coating of polytetrafluoroethylene permanently in the outlet end opening of said container pouring spout, said coating covering all portions of said outlet end opening which said liquid contacts terminally upon leaving the end of the spout.

5. A liner according to claim 1 wherein the end portion thereof overlays the terminal end of the pouring spout and said liner is fabricated completely of said polytetrafluoroethylene.

6. A liner according to claim 5 wherein said overlying portion of said liner has a substantially flat outer surface.

7. A liner according to claim 5 wherein the overlying portion of said liner has an outer surface which is outwardly curved with respect to the end of the pouring spout.

8. A liner according to claim 1 wherein the portion of said liner which terminally contacts said liquid is substantially flat.

9. A liner according to claim 1 wherein the portion of said liner which terminally contacts said liquid is outwardly curved with respect to the end of the pouring spout.

10. A liner for use in the outlet end opening of a container having a pouring spout, and for use in pouring of aqueous liquids, said liner covering a terminal end of said spout and being located such that at the terminal end of the said liquid when poured terminally contacts only the liner, the improvement wherein at least the surface of that part of said liner which said liquid by pouring terminally is in contact with consists essentially of a fluoro carbon polymer possessing similar properties as polytetrafluoroethylene in regard to aqueous liquids.

11. A liner according to claim including means for removable insertion thereof in the outlet end opening of said container pouring spout, and said liner is fabricated completely of said fluoro carbon polymers.

12. A liner according to claim 10 wherein the portion of said liner which terminally contacts said liquid is substantially flat.

13. A liner according to claim 10 wherein the portion of said liner which terminally contacts said liquid is outwardly curved with respect to the end of the pouring spout. 0 l 

1. A liner for use in the outlet end opening of a container having a pouring spout, and for use in pouring of aqueous liquid, said liner covering a terminal end of said spout and being located such that at the terminal end of the spout said liquid when poured terminally contacts only the liner, the improvement wherein at least the surface of that part of said liner which said liquid by pouring terminally is in contact with consists essentially of polytetrafluoroethylene.
 2. A liner according to claim 1 including means for removable insertion thereof in the outlet end opening of said container pouring spout.
 3. A liner according to claim 1, said liner being permanently mounted in the outlet end opening of said container pouring spout.
 4. A liner according to claim 1, said liner comprising a coating of polytetrafluoroethylene permanently in the outlet end opening of said container pouring spout, said coating covering all portions of said outlet end opening which said liquid contacts terminally upon leaving the end of the spout.
 5. A liner according to claim 1 wherein the end portion thereof overlays the terminal end of the pouring spout and said liner is fabricated completely of said polytetrafluoroethylene.
 6. A liner according to claim 5 wherein said overlying portion of said liner has a substantially flat outer surface.
 7. A liner according to claim 5 wherein the overlying portion of said liner has an outer surface which is outwardly curved with respect to the end of the pouring sPout.
 8. A liner according to claim 1 wherein the portion of said liner which terminally contacts said liquid is substantially flat.
 9. A liner according to claim 1 wherein the portion of said liner which terminally contacts said liquid is outwardly curved with respect to the end of the pouring spout.
 10. A liner for use in the outlet end opening of a container having a pouring spout, and for use in pouring of aqueous liquids, said liner covering a terminal end of said spout and being located such that at the terminal end of the said liquid when poured terminally contacts only the liner, the improvement wherein at least the surface of that part of said liner which said liquid by pouring terminally is in contact with consists essentially of a fluoro carbon polymer possessing similar properties as polytetrafluoroethylene in regard to aqueous liquids.
 11. A liner according to claim 10 including means for removable insertion thereof in the outlet end opening of said container pouring spout, and said liner is fabricated completely of said fluoro carbon polymers.
 12. A liner according to claim 10 wherein the portion of said liner which terminally contacts said liquid is substantially flat.
 13. A liner according to claim 10 wherein the portion of said liner which terminally contacts said liquid is outwardly curved with respect to the end of the pouring spout. 